Warmoth Bass VI
 

I am planning on making a Bass VI out of Warmoth parts. What would be an appropriate bridge to buy? What pickups should I use? I also don't know what tuning pegs to use. All things being equal, I don't know much at all.

The original used strat pickups. I'm not sure about the bridge. I know it was a tremolo.

If you use EMG or Bartolini pickups, you don't have to pay too much attention to the bridge spacing (they use bar magnets). That said, its best to choose the pickups, the routing and the bridge at the same time.
I used a Hipshot Bridge with 16mm spacing and had to have my pickups custom made because I chose the EMG/Bart routing pattern in my body. Carey Nordstrom custom made my pickups in the EMG/Bart size with 16mm spacing. I can highly recommend Nordstrand Fat Stacks.
I used Hipshot UltraLite HBy6 Tuners. Gotoh cost less.
Make sure your bridge can be grounded with the pickups, pots, etc.